Yeah, I haven't gotten Dark Arts yet. So far, a simple Unleash, maybe two, then rotate between targets and pop a little aggro on each is usually pretty sufficient to tank most trash mobs. Boss fights aren't much more difficult. So far, holding aggro is almost boring. I do relatively decent damage even with grit but putting on Darkside without having Dark arts is just a MP drain that may prevent me from using Unleash when something happens. Shrug. That's how it seems so far.